Radio fingerprinting techniques, also known as Radio Pattern Matching or Radio Signature positioning, represent a family of Path Loss based technologies that rely on matching the Radio Frequency (RF) environment (as experienced by a UE) to the known or estimated or otherwise mapped characteristics of the larger RF System in which the UE is operating. Information from the UE, including measurements of neighbor cell signal strengths, time delay and other network parameters, form the basis of the RF environment to be compared to the established system database. The intent of this approach is to mitigate the negative impacts of anomalies within the RF environment that challenge the accuracy of trilateration technologies (e.g., multipath and reflection).
There are growing market segments for location services that require both location accuracy and user transparency (Government Surveillance and Lawful Intercept); these services cannot be addressed with location technologies that require UE support or modification (including assisted GNSS (A-GNSS), observed time difference of arrival (OTDOA), etc.). Additionally, Emergency Service applications require a level of location accuracy that cannot be met with Cell-ID and RTT. The potential benefits of fingerprinting and the relative ease with which this location method can be adopted in the Universal Terrestrial Radio Access Network (UTRAN) indicate that it is appropriate that the technology be included in the UTRAN to support the services noted above, as well as for cooperative deployment with satellite-based systems (A-GPS, A-GNSS, etc.) to support “Hybrid” location technologies for Location Based Services (LBS).
Fingerprinting positioning methods rely on “fingerprint” data stored in a database for multiple different locations in the wireless network, where a location of a UE is determined based on comparisons between measurements made by the UE and the stored fingerprint data. For example, a location server determines the location of the UE by determining which set of stored fingerprint data most closely match the measurements made by the UE. The location server then determines the location of the UE based on the location coordinates corresponding to the most closely matching fingerprint data.
The accuracy of fingerprinting techniques relies on the accuracy of the stored fingerprint data, and the resolution provided by the various data points of the stored data. Conventional techniques typically rely on manual data collection for populating the fingerprint database. For example, an operator may go into the field with a GPS-enabled cellular telephone to collect new fingerprint data for multiple new locations in the wireless network. Such manual data collection methods are time consuming and expensive. Thus, there is an interest in cost-effective and time-efficient techniques that facilitate the population of a fingerprint database so as to achieve a desired accuracy.